1. Field of the Invention
The present invention relates to an image forming apparatus such as a copying machine and the like.
2. Related Background Art
Conventionally, in image forming apparatuses such as copying machines, a fixing device including a heat pressing roller has been used as a fixing means for fixing an image to a transfer sheet. Since the fixing device including such a heat pressing roller utilizes a heat source having great consumption of electricity such as a halogen heater, it is very difficult to reduce consumption of electricity of the entire image forming apparatus.
Particularly, continuous copying operations are effected by using a copying machine having a fluorescent lamp as an illumination light source of an original scanning portion, since consumption of electricity becomes great during back scanning for returning an original scanning body from a scan finishing position to a home position, maximum consumption of electricity of the machine may not be suppressed within a desired range. The reason is that it takes a long time for the fluorescent lamp to stabilize a light amount after the lamp is turned ON so that the fluorescent lamp cannot be turned OFF during the back scanning, and a shifting speed of the original scanning body in the back scanning is faster than in forward scanning, with the result that consumption of electricity of a drive motor during the back scanning becomes great.
Due to such great consumption of electricity in the back scanning of the original scanning body, the consumption of electricity of the entire machine may not be suppressed within the desired range.